Method and apparatus for connecting tubulars using a top drive

ABSTRACT

An apparatus for facilitating the connection of tubulars, said apparatus comprising a winch ( 15 ), at least one wire line ( 4, 5 ) and a device ( 2 ) for gripping a tubular ( 3 ), the arrangement being such that, in use, the winch ( 15 ) can be used to winch said at least one wire ( 4, 5 ) and said device ( 2 ) to position a tubular ( 3 ) below said top drive.

This invention relates to a method and apparatus for facilitating theconnection of tubulars using a top drive and is, more particularly butnot exclusively, for facilitating the connection of a section or standof casing to a string or casing.

In the construction of wells such as oil or gas wells, it is usuallynecessary to line predrilled holes with a string of tubulars known ascasing. Because of the size of the casing required, sections or standsof say two sections of casing are connected to each other as they arelowered into the well from a platform. The first section or stand ofcasing is lowered into the well and is usually restrained from fallinginto the well by a spider located in the platform's floor. Subsequentsections or stands of casing are moved from a rack to the well centreabove the spider. The threaded pin of the section or stand of casing tobe connected is located over the threaded box of the casing in the wellto form a string of casing. The connection is made-up by rotationtherebetween.

It is common practice to use a power tong to torque the connection up toa predetermined torque in order to perfect the connection. The powertong is located on the platform, either on rails, or hung from a derrickon a chain. However, it has recently been proposed to use a top drivefor making such connection.

Prior to the present invention, pipe handling devices moved pipes to beconnected to a tubular string from a rack to the well centre usingarticulated arms or, more commonly, a pipe elevator suspended from thedrilling tower.

The present invention provides an alternative to these devices.

Accordingly, a first aspect of the present invention provides anapparatus for facilitating the connection of tubulars, said apparatuscomprising a winch, at least one wire line and a device for gripping atubular the arrangement being such that, in use, the winch can be usedto winch said at least one wire and said device to position a tubularbelow said top drive.

Further features are set out in claims 2 to 6.

According to a second aspect of the present invention there is provideda method of facilitating the connection of tubulars using a top driveand comprising the steps of attaching at least one wire to a tubular,the wire depending from the top drive or from a component attachedthereto, and winching the wire and the tubular upwards to a positionbeneath the top drive.

According to a third aspect of the present invention there is providedan apparatus for facilitating, the connection of tubulars using a topdrive, said apparatus comprising an elevator and a pair of bails,characterised in that said elevator is, in use, movable in relation tosaid pair of bails.

According to a fourth aspect of the present invention there is providedan apparatus for facilitating the connection of tubulars using a topdrive, said apparatus comprising, an elevator (102) and a pair of bails(103, 104), characterised in that said elevator (102) is, in use,movable relative to said pair of bails (103, 104).

For a better understanding of the present invention and in order to showhow the same may be carried into effect reference will now be made, byway of example, to the accompanying drawings in which:

FIGS. 1a to 1 e are perspective views of an apparatus in accordance witha first embodiment of the present invention at various stages ofoperation; and

FIGS. 2a to 2 d are perspective views of an apparatus in accordance witha second embodiment of the invention at various stages of operation.

Referring to FIGS. 1a to 1 e there is shown an apparatus which isgenerally identified by reference numeral 1.

The apparatus 1 comprises a clamp 2 for retaining a tubular 3. The clamp2 is suspended on wires 4, 5 which are connected thereto on opposingsides thereof. The wire 5 passes through an eye 6 in lug 7 which isattached to a spherical bearing in arm 8 of a suspension unit 9 at thepoint at which the arm 8 is connected to a hydraulic motor 10. The wireis connected to the hydraulic motor 10 in a corresponding manner. Thesuspension unit 9 is of a type which enables displacement of the tubular3 when connected to a tool 17 (see below), relative to a top drive 13,along a number of different axes. The wires 4, 5 pass across thesuspension unit 9 and over pulley wheels 11 which are rotatably arrangedon a plate 12. The plate 12 is fixed in-relation to a top drivegenerally identified by reference numeral 13. The wires 4, 5 then passover drums 14 to which the wires 4, 5 are also connected. The drums 14are rotatable via a hydraulic winch motor 15.

In use, the clamp 2 is placed around a tubular below a box 16 thereofThe hydraulic winch motor 15 is then activated, which lifts the tubular3 (conveniently from a rack) and towards a tool 17 for gripping thetubular 3 (FIG. 1b). The tubular 3 encompasses the tool 17 at whichpoint the hydraulic winch motor 15 is deactivated FIG. 1c). During thisoperation the elevator 18 is held away from the tool 17 by piston andcylinders 19, 20 acting on bails 21 and 22. The suspension unit 9 allowsthe hydraulic motor 10 and the arrangement depending therebelow to movein vertical and horizontal planes relative to the top drive 13. The eyes6 in lugs 7 maintain the wires 4 and 5 in line with the tubular 3 duringany such movement. The tool 17 may now be used to connect the tubular tothe tubular string. More particularly, the tool may be of a type whichis inserted into the upper end of the tubular, with gripping elements ofthe tool being radially displaceable for engagement with the inner wallof the tubular so as to secure the tubular to the tool. Once the tool issecured to the tubular, the hydraulic motor 10 is activated whichrotates the tool 17 and hence the tubular 3 for engagement with atubular string held in a spider.

The clamp 2 is now released from the tubular 3, and the top drive 13 andhence apparatus 1 is now lifted clear of the tubular 3. The elevator 18is now swung in line with the apparatus 1 by actuation of the piston andcylinders 19 and 20 (FIG. 1d).

The top drive 13 is then lowered, lowering the elevator 18 over the box16 of the tubular 3. The slips in the elevator 18 are then set to takethe weight of the entire tubular string. The top drive is then raisedslightly to enable the slips in the spider to be released and the topdrive is then lowered to introduce the tubular string into the borehole.

Referring to FIGS. 2a to 2 d there is shown an apparatus which isgenerally identified by reference numeral 101.

The apparatus 101 comprises an elevator 102 arranged at one end of bails103, 104. The bails 103, 104 are movably attached to a top drive 105 viaaxles 106 which are located in eyes 107 in the other end of the bails103, 104. Piston and cylinders 108, 109 are arranged between the topdrive 105 and the bails. One end of the piston and cylinders 108, 109are movably arranged on axles 110 on the top drive. The other end of thepiston and cylinders 108, 109 are movably arranged on axles 111, 112which are located in lugs 113, 114 located approximately one-third alongthe length of the bails 103, 109.

The elevator 102 is provided with pins 115 on either side thereof andprojecting therefrom. The pins 115 are located in slots 116 and 116 a. Apiston 117, 118 and cylinder 119, 120 are arranged in each of the bails103, 104. The cylinders are arranged in slot 121, 122. The piston 117,118 are connected at their ends to the pins 115. The cylinders 119, 120are prevented from moving along the bails 103, 104 by cross members 123and 124. A hole is provided in each of the cross members to allow thepistons to move therethrough.

In use, a tubular 125 is angled from a rack near to the well centre. Thetubular may however remain upright in the rack. The clamp 102 is placedaround the tubular below a box 126 (FIG. 2a). The top drive is raised ona track on a derrick. The tubular is lifted from the rack and thetubular swings to hang vertically (FIG. 2b). The piston and cylinders108, 109 are actuated, extending the pistons allowing the bails 103, 104to move to a vertical position. The tubular 125 is now directly beneatha tool 127 for internally gripping and rotating the tubular 125 (FIG.2c). The pistons 117, 118 and cylinders 119, 120 are now actuated. Thepins 115 follow slot 116 and the clamp 102 moves upwardly, lifting thetubular 125 over the tool 127 (FIG. 2d). The tool 127 can now beactuated to grip the tubular 125.

At this stage the elevator 102 is released and the top drive 105 loweredto enable the tubular 125 to be connected to the string of tubulars inthe slips and torqued appropriately by the top drive 105.

The pistons 117, 118 and cylinders 119, 120 are meantime extended sothat after the tubular 125 has been connected the top drive 105 can beraised until the elevator 102 is immediately below the box. The elevator102 is then actuated to grip the tubular 125 firmly. The top drive 105is then raised to lift the tubular string sufficiently to enable thewedges in the slips to be withdrawn. The top drive 105 is then lower tothe drilling platform, the slips applied, the elevator 102 raised forthe tubular 125 and the process repeated.

I claim:
 1. An apparatus for facilitating the connection of tubularsusing a top drive and comprising: a suspension unit (9) for coupling atubular (3) to the top drive, the suspension unit (9) having a staticpart fixed with respect to a top drive and a dynamic part movablerelative thereto; and a winch (15) located on said static part of saidsuspension unit (9), at least one wire (4, 5), and a device (2) forgripping the tubular (3), the arrangement being such that, in use, thewinch (15) can be used to winch said at least one wire (4, 5) and saiddevice (2) to position the tubular (3) below said top drive.
 2. Anapparatus as claimed in claim 1, comprising a guide (7) located on saiddynamic part (8) of said suspension unit (9).
 3. An apparatus as claimedin claim 2, comprising a pulley wheel (11) on said static part of saidsuspension unit (9).
 4. A method of facilitating the connection oftubulars using a top drive having a suspension unit (9) for coupling atubular (3) to the top drive, the suspension unit (9) having a staticpart fixed with respect to a top drive and a dynamic part movablerelative thereto, the static part defining a winch, the methodcomprising the steps of attaching at least one wire to a tubular, thewire depending from the static part of said suspension unit, andwinching the wire and the tubular upwards to a position beneath the topdrive.
 5. An apparatus for facilitating the connection of tubulars usinga top drive, said apparatus comprising: an elevator, and a pair ofbails, wherein said elevator is movable along said pair of bails.
 6. Anapparatus as claimed in claim 5, further comprising a piston (117, 118)and cylinder (119, 120) operatively connected between said pair of bails(103, 104) and said elevator (102).
 7. An apparatus as claimed in claim6, wherein said piston (117, 118) and cylinder (119, 120) arepneumatically or hydraulically operable.
 8. An apparatus forfacilitating the connection of tubulars using a top drive, saidapparatus comprising: an elevator (102) having pins (115); and a pair ofbails (103, 104) comprising slots (116, 116 a) in which said pins (115)are disposed, wherein said elevator (102) is movable along said pair ofbails (103, 104).
 9. An apparatus for facilitating the connection oftubulars using a top drive, said apparatus comprising: an elevator(102); and a pair of bails (103, 104) attached to an axle (106) disposedon the top drive and are movable thereabout, wherein said elevator (102)is movable along said pair of bails (103, 104).
 10. An apparatus forfacilitating the connection of tubulars using a top drive, saidapparatus comprising: an elevator (102); a pair of bails (103, 104)attached to an axle (106) disposed on the top drive and are movablethereabout, wherein said elevator (102) is movable along said pair ofbails (103, 104); and at least one piston and cylinder (108, 109) formoving said pair of bails (103, 104).
 11. A method for facilitating theconnection of tubulars using a top drive, said method comprising: usingan elevator to move a tubular to a position below said top drive,wherein the elevator is connected to the top drive using a pair of bailsand wherein the elevator is movable along said pair of bails.
 12. Amethod of claim 11, wherein the elevator moves said tabular towards oraway from a tool for gripping said tubular.
 13. A method for connectinga first tubular and a second tubular using a top drive, comprising:gripping the first tubular with a clamp; raising the first tubulartoward a tool; holding the first tubular with the tool; connecting thefirst tubular to the second tubular; releasing the first tubular fromthe clamp and the tool; gripping the first tubular with an elevator; andlower the first tubular.
 14. The method of claim 13, wherein the secondtubular is held by a spider.
 15. The method of claim 13, whereinconnecting the first tubular to the second tubular comprises rotatingthe first tubular relative to the second tubular.
 16. The method ofclaim 13, wherein the clamp and the elevator are both connected to thetop drive.
 17. The method of claim 16, wherein the clamp is connected tothe top drive using at least one wire.
 18. The method of claim 16,wherein the elevator is connected to the top drive using at least onebail.